Aromatic polyamides have been prepared by condensing aromatic diacid chlorides and aromatic diamines in polar aprotic solvents. In practice, the variety of aromatic polyamides which can be prepared by this process is limited by the small number of commercially available diacid chlorides. It would be desirable to provide a process capable of producing a wider variety of aromatic polyamides.
Japanese Kokai 123823, published May 16, 1989, discloses a method for the production of aromatic polyamides by reacting an aromatic diamine, an aromatic dibromide and CO in the presence of palladium catalyst in an organic solvent at atmospheric pressure. This method produces low molecular weight aromatic polyamides having inherent viscosities in the range from about 0.2 to about 0.8 dL/g. However, as indicated by Yang in "Aromatic High Strength Fibers", Wiley, New York, 1989, it is known that polyamides having particularly useful mechanical properties exhibit inherent viscosities greater than 1.0 dL/g. Additionally, the method described in Japanese Kokai 123823 is undesirably slow. Thus, it would be desirable to prepare aromatic polyamides having higher molecular weights and higher inherent viscosities at faster rates of formation.